Effectiveness and safety of morphine sulfate extended-release capsules in patients with chronic, moderate-to-severe pain in a primary care setting

J Pain Res. 2011:4:373-84. doi: 10.2147/JPR.S23024. Epub 2011 Nov 8.

Abstract

Background: The purpose of this study was to determine the effectiveness and safety of morphine sulfate extended-release capsules among primary care patients with chronic, moderate-to-severe pain using a universal precautions approach that assessed and monitored risk for opioid misuse and abuse.

Methods: This open-label, uncontrolled, multicenter, prospective study was conducted in primary care centers (n = 281) and included opioid-naïve and opioid-experienced patients with either a pain score ≥4 (0 = no pain, 10 = pain as bad as you can imagine), or with unacceptable side effects while taking opioids. The patients were treated with morphine sulfate extendedrelease capsules for up to four months. Patient-rated pain intensity (worst, least, average) over the past 24 hours (0-10 scale), pain interference with seven activities of daily living (0 = no interference, 10 = completely interferes), and adverse events were recorded.

Results: Of 1487 patients who filled at least one prescription, 561 (38%) completed the study. Patients were primarily white (87%) and female (57%); 92% had pain for more than one year; and 79% were opioid-experienced. Median age was 52 years. Decreases in mean (± standard deviation) average pain scores (baseline 6.2 ± 2.3) were -0.8 ± 2.2 at visit 2 (5-14 days later), and -1.6 ± 2.3 and -1.7 ± 2.2 at visits 3 and 4 (spaced 3-4 weeks apart), respectively, and -1.1 ± 2.4 at visit 5 (included patients withdrawn from the study who were no longer taking the study drug). A similar trend was observed for worst pain and least pain scores and for pain interference with activities. Fifty-one percent of the safety population patients and 81% in the completer population reported being satisfied or very satisfied with the study treatment. Most common adverse events were typical of opioids, ie, constipation (14%), nausea (11%), vomiting (5%), and somnolence (5%).

Conclusion: The results suggest that pain outcomes improved in patients with chronic, moderate-to-severe pain receiving morphine sulfate extended-release capsules within the context of a structured universal precautions approach in the primary care setting.

Keywords: analgesics; opioids; pain assessment; primary care; substance abuse; universal precautions.